The invention relates to an adjustment mechanism for a grinding wheel on a sharpening machine for saws, comprising
a carrier member reciprocable strokewise transversely of the axis of the grinding wheel, PA1 a carriage supported on the carrier member parallel to the axis of the grinding wheel, PA1 a bearing member supported for advancement on the carriage, likewise parallel to the axis of the grinding wheel, PA1 a shaft journalled in the bearing member and supporting the grinding wheel, PA1 a carriage drive by means of which the carriage is reciprocable relative to the carrier member in timed relation with said carrier member's movements, PA1 and a front and a back end stop for limiting the adjustment of the carriage.
In known adjustment mechanism of this type, the carriage drive has the task of bringing the carriage for each working stroke of the carrier member into a position in which the grinding wheel abrades material, for example, from the cutting edge or back of a tooth to be worked; for the subsequent return stroke of the carrier member, the carriage drive brings the carriage into a retracted position in which the grinding wheel no longer touches the tooth. It is of no importance in connection with the present invention whether the carrier member is guided on a rectilinear path reciprocable along the tooth cutting edge or the tooth back, or whether it is arranged in the manner of a pendulum so that the grinding wheel can swing through a tooth space transversely of the saw blade plane each time. If a saw blade with different teeth is to be ground, for example a saw blade with alternating rough-cutting teeth of greater height and finish-cutting teeth of lesser height, it is then necessary in saw sharpening machines with known adjustment mechanisms of the kind specified to grind the rough-cutting teeth on the one hand and the finish-cutting teeth on the other hand during different passages or revolutions of the saw blade and to change the advance of the bearing member in relation to the carriage appropriately for each passage. This is time-consuming, especially as it is usually necessary to grind chamfers in addition to the tooth back faces on rough cutting teeth, for which purpose another advance of the bearing member relative to the carriage is necessary.
It is therefore an object of the invention to further develop an adjusting mechanism of the kind described at the outset so that different teeth, for example, rough-cutting and finish-cutting teeth, can be ground directly after each other in one and the same passage or revolution of the saw blade.